Catalysts' influence on thermochemical decomposition of waste tires

Abstract

In this article, correlation between the influence of catalysts on waste tires pyrolysis at small‐ and laboratory‐scale installation are highlighted. Kinetic and thermodynamic parameters of tires rubber thermochemical transformations were evaluated using thermogravimetric analyses (TGA). For that purpose, Zeolite (ZSM‐5), alumina (Al 2 O 3 ), calcium carbonate (CaCO 3 ), and magnesium oxide (MgO) were used as catalyst. It was found that all catalysts induce a delayed onset of pyrolytic process and MgO and CaCO 3 significantly reduced the activation energy ( E a ) from 246.89 kJ ⋅ mole −1 (thermal pyrolysis) to 121.82 and 128.34 kJ ⋅ mole −1 , respectively. At laboratory scale, a fixed‐bed reactor was used to distinguish how the contact manner between tires and catalysts influences the yield of pyrolysis products as well as the gas quality. It was proved that CaCO 3 and Al 2 O 3 are the most suitable catalysts for increasing the gas fraction, while the MgO promotes the formation of liquid fraction. © 2017 American Institute of Chemical Engineers Environ Prog, 36: 1560–1567, 2017